Cast wheel mold cavity exhaust device

ABSTRACT

The invention discloses a cast wheel mold cavity exhaust device, includes a bottom mold, a side mold, a top mold, an upper exhaust pin and a lower exhaust pin. A boss is provided on the bottom mold corresponding to the window molding part of a wheel, a groove cavity is provided on the top mold corresponding to the boss, a step hole is provided on the boss of the bottom mold, and the lower exhaust pin is installed in the step hole.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No.2017101632731, filed on Mar. 19, 2017, which is hereby incorporated byreference in its entirety.

TECHNICAL FIELD

The present application relates to the field of molds, and specificallyto a cast wheel mold cavity exhaust device.

BACKGROUND ART

In the wheel casting process, the mold system is in the atmosphericenvironment, and if air in the mold cavity is not exhausted thoroughlyin the molding process, the defects of oxide inclusions, air holes andthe like easily occur in a casting, thus influencing the productquality. Besides, the defects reduce the density of a casting structure,and reduce the effective sectional area, so that the mechanicalproperties are seriously substandard, and the safety of a vehicle isgreatly influenced. Thus, how to realize smooth exhaust of the moldcavity is quite important for the casting quality of a wheel, andpositive and effective measures must be taken to eliminate an airproofarea of the mold cavity and fully fill molten aluminum, so that variousair defects can be effectively solved and the product quality can beimproved to adapt to the increasingly fierce market competition.

SUMMARY OF THE INVENTION

The present application is aimed at providing a device capable ofimproving the exhaust effect of a wheel casting mold.

The technical solution of the present application is that a cast wheelmold cavity exhaust device includes a bottom mold, a side mold, a topmold, an upper exhaust pin and a lower exhaust pin. A boss is providedon the bottom mold corresponding to the window molding part of a wheel,a groove cavity is provided on the top mold corresponding to the boss,and a clearance is provided between the fitting surfaces of the boss andthe groove cavity.

A step hole is provided on the boss of the bottom mold. The lowerexhaust pin is installed in the step hole, and the lower exhaust pin isconfigured as a cylinder and is connected with a mold body. The part,protruding the profile of the mold, of the lower exhaust pin is polishedto be smooth, and flaky exhaust lines are arranged axially at theworking part of the lower exhaust pin. Vent grooves distributeddivergently are formed on the profile of the boss by taking the lowerexhaust pin as a center, and the tail ends of the vent grooves extend tothe outer edge of the boss.

Another step hole is provided in the groove cavity of the top mold. Theupper exhaust pin is installed in the step hole, and the upper exhaustpin is configured as a cylinder and is connected with the mold body. Thepart, protruding the profile of the mold, of the upper exhaust pin ispolished to be smooth, and flaky exhaust lines are arranged axially atthe working part of the upper exhaust pin. Vent grooves distributeddivergently are formed on the profile of the groove cavity by taking theupper exhaust pin as a center, and the tail ends of the vent groovesextend to the outer edge of the groove cavity.

The clearance provided between the fitting surfaces of the boss and thegroove cavity is 0.2-0.5 mm.

The quantity of the lower exhaust pin is 1-5, and the quantity of theupper exhaust pin is 1-5.

On the upper exhaust pin, the quantity of the flaky exhaust lines is4-6, and the widths of the flaky exhaust lines are 0.2-0.4 mm. On thelower exhaust pin, the quantity of the flaky exhaust lines is 4-6, andthe widths of the flaky exhaust lines are 0.2-0.4 mm.

The depths of the vent grooves distributed divergently on the profile ofthe boss are 0.5-1.0 mm, and the included angles are 60°-90°.

The present application provides two exhaust channels, respectively:mold cavity-groove cavity-upper exhaust pin-air; mold cavity-boss-lowerexhaust pin-air. The channel area of air exhaust of the mold cavity isenlarged, the exhaust effect is strengthened, and a clean mold cavityenvironment is provided for mold filling and solidification of moltenaluminum. By designing double structures of exhaust grooves and exhaustpins on the top mold and the bottom mold, active exhaust of the moldcavity is realized, the smoothness of air circulation is improved, theairproof area is eliminated, the defects easily occurring in a casting,such as oxide inclusions, air holes and the like, are overcome, theyield is greatly improved, and high-quality production of wheels isensured.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of a cast wheel mold cavity exhaust deviceof the present application.

FIG. 2 is a schematic top view of the cast wheel mold cavity exhaustdevice of the present application.

In figures: 1—bottom mold, 11—boss, 2—side mold, 3—top mold, 31—groovecavity, 4—upper exhaust pin, 5—lower exhaust pin, 51—flaky exhaust line,6—vent groove.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIGS. 1 and 2, an improved wheel casting mold cavity exhaustdevice of the embodiment includes a bottom mold 1, a side mold 2, a topmold 3, an upper exhaust pin 4 and a lower exhaust pin 5; a boss 11 isprovided on the bottom mold 1 corresponding to the window molding partof a wheel, a groove cavity 31 corresponding to the boss 11 is machinedon the top mold 3, the profiles of the boss 11 and the groove cavity 31do not contact with each other and have a clearance of 0.2-0.5 mm,casting burrs are easily formed if the clearance is too large, and theexhaust effect is influenced if the clearance is too small; a step holeis machined on the boss 11 of the bottom mold, and the lower exhaust pin5 is installed in the hole and connected with a mold body by spotwelding or by a bolt; a step hole is also drilled in the groove cavity31 of the top mold, and the upper exhaust pin 4 is installed in the holeand connected with the mold body by spot welding or by a bolt; thequantity of the exhaust pin is determined according to the size of thewindow, and is generally 1-5; the upper exhaust pin 4 and the lowerexhaust pin 5 are designed as a cylinder structure facilitatinginstallation, and the part protruding the profile of the mold shall bepolished to be smooth so as not to influence mold assembly; generally4-6 flaky exhaust lines 51 are cut at the working parts of the upperexhaust pin 4 and the lower exhaust pin 5, and have the widths of0.2-0.4 mm, thus ensuring the exhaust effect; vent grooves 6 distributeddivergently are machined on the profile of each of the boss 11 and thecavity 31 by taking the exhaust pin as a center, the vent grooves 6 havedepths of 0.5-1 mm and included angles of 60-90°, and the tail ends ofthe vent grooves 6 extend to the edge; two active exhaust channels areformed in the above design: I, mold cavity-groove cavity-upper exhaustpin-air, and II, mold cavity-boss-lower exhaust pin-air, so that thechannel area of air exhaust of the mold cavity is enlarged, the exhausteffect is strengthened, and a clean mold cavity environment is providedfor mold filling and solidification of molten aluminum.

By designing double structures of exhaust grooves and exhaust pins onthe top mold and the bottom mold, active exhaust of the mold cavity isrealized, the smoothness of air circulation is improved, the airproofarea is eliminated, the defects easily occurring in a casting, such asoxide inclusions, air holes and the like, are overcome, the yield isgreatly improved, and high-quality production of wheels is ensured.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described in orderto explain certain principles of the invention and their practicalapplication, to thereby enable others skilled in the art to make andutilize various exemplary embodiments of the present invention, as wellas various alternatives and modifications thereof. It is intended thatthe scope of the invention be defined by the Claims appended hereto andtheir equivalents.

1. A cast wheel mold cavity exhaust device, comprising a bottom mold, aside mold, a top mold, an upper exhaust pin and a lower exhaust pin,wherein a boss is provided on the bottom mold corresponding to a windowmolding part of a wheel, a groove cavity is provided on the top moldcorresponding to the boss, and a clearance is provided between fittingsurfaces of the boss and the groove cavity; a first step hole isprovided on the boss of the bottom mold, the lower exhaust pin isinstalled in the first step hole, the lower exhaust pin is configured asa cylinder and is connected with a mold body, a part, protruding aprofile of the mold, of the lower exhaust pin is polished to be smooth,and flaky exhaust lines are arranged axially at a working part of thelower exhaust pin; vent grooves distributed divergently are provided ina profile of the boss by taking the lower exhaust pin as a center, andtail ends of the vent grooves extend to an outer edge of the boss; asecond step hole is provided in the groove cavity of the top mold, theupper exhaust pin is installed in the second step hole, the upperexhaust pin is a cylinder and is connected with the mold body, a part,protruding a profile of the mold, of the upper exhaust pin is polishedto be smooth, and flaky exhaust lines are arranged axially at a workingpart of the upper exhaust pin; vent grooves distributed divergently areformed on a profile of the groove cavity by taking the upper exhaust pinas a center, and tail ends of the vent grooves extend to an outer edgeof the groove cavity.
 2. The cast wheel mold cavity exhaust deviceaccording to claim 1, wherein the clearance provided between the fittingsurfaces of the boss and the groove cavity is 0.2-0.5 mm.
 3. The castwheel mold cavity exhaust device according to claim 1, wherein aquantity of the lower exhaust pin is 1-5, and a quantity of the upperexhaust pin is 1-5.
 4. The cast wheel mold cavity exhaust deviceaccording to claim 1, wherein a quantity of the flaky exhaust lines onthe upper exhaust pin is 4-6, and widths of the flaky exhaust lines are0.2-0.4 mm; a quantity of the flaky exhaust lines on the lower exhaustpin is 4-6, and widths of the flaky exhaust lines are 0.2-0.4 mm.
 5. Thecast wheel mold cavity exhaust device according to claim 1, whereindepths of the vent grooves distributed divergently in the profile of theboss are 0.5-1.0 mm, and included angles are 60°-90°.